1. Field of the Invention
The present invention relates to a multiple frequency array antenna for mobile communication system.
2. Description of the Prior Art
There have been proposed various improvements concerning the multiple frequency array antenna in the field of the mobile communication.
Referring to FIG. 7, an example of a double frequency array antenna is explained, which is disclosed in "Two band cellular antenna" (M. Bodley et al., 1997 IEEE MTT-s International Topical Symp. on Technologies for Wireless Applications pp93-98).
A plurality of arrayed patch antennas 14 for frequency F1 in the above-mentioned two band cellular antenna is connected with distribution line 16 on substrate 17, and is fed by distribution line 16 which is a supply system. Similarly, a plurality of arrayed patch antennas 18 for frequency F2 is fed by the feeder system of distribution line 19 on substrate 17. These are guided to a two way supply network.
However, in the above-mentioned reference, the size of the whole device is too large for the mobile communication equipment, because the space for two or more antenna stacks according to the frequency multiplicity is required on the same substrate.